Somehow detecting coin in grass (8)
I believe the answer is:
scenting
'somehow detecting' is the definition.
I can't judge whether this definition defines the answer.
'coin in grass' is the wordplay.
'coin' becomes 'cent' (cent is a kind of coin).
'in' indicates putting letters inside.
'grass' becomes 'sing' (both can mean to act as an informant).
'cent' going within 'sing' is 'SCENTING'.
Can you help me to learn more?
(Other definitions for scenting that I've seen before include "discerning" , "Catching the smell of" .)